#include <stdio.h>
float fun(int  n)
{
	int i,j=2,s=1;
	float sum=0;
	for(i=0;i<n;i++,j++)
	{
		sum=1.0/s+sum;
		s=s+j;
	}
	return sum;
}
int main()
{	int n; float s;
	printf("\nPlease enter n:"); 
	scanf("%d", &n);
	s = fun(n);
	printf("the result is: %f\n", s);
	return 0;
}
